Abstract: Neutrophils express receptors that specifically recognized microorganisms and viruses and efficiently ingest and destroy these pathogens. Moreover, antigen presenting cells as macrophages and dendritic cells present the microbial antigens via MHC class II molecules, resulting in the activation of specific CD4 T cells. Since neutrophils have a short lifespan and are highly susceptible to apoptosis, their role in antigen presentation has been questioned. However, various pro-inflammatory cytokines such as IL-1, IL-6, TNF- and IFN- produced at the site of inflammation activate neutrophils and suppress apoptotic death. These cytokine activated-neutrophils show enhanced expression of cell surface molecules and become as competent as dendritic cells and macrophages in the ability of antigen presentation. Up until now, the role of neutrophils has been focused only on the phagocytosis-mediated microbial activity. However, neutrophils are as competent as dendritic cells and macrophages in antigen presentation. An updated review of the old concept regarding the roles of neutrophils in biodefense is necessary. In the present review on the role of neutrophils, we describe both the classic innate and acquired immunity.